The LED technology used in a light source has the advantages such as high luminous intensity, long service lifetime, and high efficiency and energy saving, therefore, this technology is widely used and gradually replacing the conventional illumination modes. In the field of medical use, the LED technology also plays an active role, for instance, the LED technology is applied to modern surgical shadowless lamp, medical examination lamp and dentist lamp, and the LED illumination technology also provides to users sufficient illumination effects adapted to various medical circumstances while simplifying development and maintenance of these medical equipment. Some current in-service illumination devices for medical use are configured with LED as light source and corresponding reflecting structure and lens, while as the light source and the reflecting structure, or the light source and the lens are always configured integrally, such illumination device can only be adapted to one circumstance, and if the light source or the lens needs to be changed, the whole illumination device should be replaced, which not only limits the application circumstances of this medical illumination device, but also results in a high cost of development and maintenance of this illumination device for medical use.